Well tool construction



Feb. 23, 1937. J. c. WRIGHT ET AL WELL TOOL CONS TRUCT ION Filed NOV. 26, 1934 f/Wnvro/as Jess: C. MP/6H7 Joy fl. Harman ATTORNEY Patented Feb. 23, 1937 UNITED STATES PATENT OFFICE WELL TOOL CONSTRUCTION Application November 26, 1934, Serial No. 754,762

Claims.

This invention relates to well drilling tools and relates more particularly to an improved construction for tools and equipment employed in the drilling of deep wells such as oil wells and gas wells. A general object of the invention is to provide a simple, practical sectional well tool whose parts or sections are dependably locked against detachment and separation.

Another object of the invention is to provide a well tool construction involving dependable means for locking the shank sections and cutters against separation and disconnection.

Another object of the invention is to provide a well tool in which the parts or sections may be tightly threaded together to their proper positions and then positively locked against unthreading.

Another object of the invention is to provide a well tool construction embodying means for positively locking the threadedly connected parts against separation that may be easily and quickly detached or removed to allow the parts to be disconnected for repair, replacement, etc.

Another object of the invention is to provide a well tool construction of the character mentioned in which a lock part is adapted to be arranged to engage a cutting part or blade of a cutting element to lock the cutting element against unthreading from the shank.

A further object of the invention is to provide an improved well tool construction of the character mentioned that is simple and inexpensive of manufacture.

The various objects and features of our invention will be fully understood from the following detailed description of a typical preferred form and application of the invention, throughout which description reference is made to the accompanying drawing, in which:

Fig. 1 is a side elevation of a well tool embodying the present invention with one quarter in longitudinal cross section. Fig. 2 is a transverse detailed sectional view taken as indicated by line 22 on Fig. 1. Fig. 3 is a transverse detailed sectional view taken as indicated by line 3-3 on Fig. 1. Fig. 4 is a fragmentary side elevation of the connected end portions of the shank sections illustrating the locking part in front elevation and Fig. 5 is a side elevation of one of the locking parts or keys.

The improved construction provided by this invention is adapted to be embodied in well tools and equipment varying considerably in character. Throughout the following detailed disclosure we will describe the invention embodied in a typical preferred form of drilling tool for use in the rotary method of well drilling, it being understood that the invention is not to be construed as restricted to the specific form or application about to be described.

The well drilling tool illustrated in the drawing and embodying the invention includes, generally, a sectional shank I0, means II for locking the sections of the shank against disconnection, a cutter I2 on the lower end of the shank l0, means l3 for locking the cutter I2 against detachment from the shank, a reaming or bore enlarging cutter M on the shank ID and means l5 for locking the cutter I4 against detachment from the shank.

The shank I0 is an elongate sectional structure for carrying the cutters l2 and H. The shank 10 may be of any desired length and may comprise any required number of parts or sections. In the particular tool illustrated in the drawing the shank I0 includes an upper section I 6 and a lower section l1. Suitable means is provided on the section It for connecting it with a drilling string of drill pipe or the like. In the drawing we have shown a tapered screw-threaded pin I8 on the upper end of the section I6 adapted to be threaded into the socket of a part on the drilling string. The upper shank section I6 carries the bore enlarging cutter l4 and has a tapered threaded portion IS on which the cutter I4 is arranged. An annular flange 2|! is provided on the section It at the upper end of the portion I9 and its lower side forms a downwardly facing abutment shoulder 2| engageable by the upper end of the cutter M. A longitudinal passage 9 is provided in the shank [0 to pass or handle the circulation fluid.

In accordance with the invention the shank sections l6 and l 1 are connected by screw threads. In the preferred construction a reduced tapered screw-threaded pin 22 is provided on the lower end of the section l6 and is threaded into a socket 23 in the upper end of the section H. The upper end of the section l6 may engage or bear upwardly against a shoulder 24 at the upper end of the pin 22. The adjacent end portions of the shank sections l6 and H are preferably of the same diameter as illustrated in the drawing. The lower end of the section I! is formed to carry the bit or cutter l2. The cutter I2 is threadedly connected with the shank section I! and the lower end of the section is provided with a tapered threaded pin 25. The pin 25 is reduced in diameter providing a downwardly facing shoulder 26 at its upper end.

The means I I for locking the shank sections I6 and Il against disconnection is such that the sections may be tightly threaded together in the usual manner and then positively locked against unthreading. In the simple form of the invention disclosed in the drawing the means II includes a plurality of circumferentially spaced projections or lugs 21 on the upper end portion of the section H. In practice there may be four equally spaced lugs 21. The lugs are elongated longitudinally of the shank and have vertical sides which may be substantially radial relative to the central longitudinal axis of the tool. The lugs 21 are preferably proportioned so that they do not contact the wall of the well bore during the operation of the drilling tool.

The means II includes slots or grooves 28 in the section I6 above its pin 22. The grooves 28 extend longitudinally of the shank section I6 and are preferably identical in shape. The upper portions 29 of the grooves 28 may have flat parallel side walls and the intermediate portions 30 of the grooves have grooved side walls provided with overhanging dove-tailed flanges 3|. The grooves 28 have lower portions 32 which extend downwardly to the shoulder 24. The portions 32 are preferably shallower than the intermediate portions 30 providing upwardly facing shoulders 33 on the bottom walls of the grooves. The portions 32 may have fiat parallel side walls flush with and forming continuations of the inner sides of the flanges 3|. The number and the circumferential spacing of the grooves 28 depend upon the number of lugs 21 provided on the sections I1. Where there are four equally spaced lugs 2! there may be two grooves 28 spaced at approximately degrees from one another. This relating of the grooves 28 with the lugs 21 insures the occurrence of a groove 28 adjacent the forward side of 2. lug 21 regardless of the relative rotative positions assumed by the sections I 6 and I! when they are threaded together.

The lock means I I includes a lock part or key 34 for arrangement in a groove 28. The key 34 is shaped to fit the groove and is adapted to project downwardly beyond the shoulder 24 to have cooperation with a lug 21. The lock part 34 is substantially rectangular in horizontal cross section and has an upper portion 35 shaped and proportioned to fit the intermediate portion 39 of the groove 28. Longitudinal dove-tailed tongues 36 are provided on the opposite side surfaces of the portion 35 to fit under and cooperate with the dove-tailed flanges 3|. The inner side of the lock part 34 is stepped or provided with a downwardly facing shoulder 31 and a downwardly facing shoulder 38. The shoulder 31 is adapted to cooperate with the shoulder 33 while the shoulder 38 may cooperate with the upper end of the shank section IT. The portion of the lock part 34 extending through the intermediate groove portion 32 may have plain flat side surfaces for cooperating with the walls of the groove to support the part 34 against lateral thrusts. The lock part 34 has a tang or tongue 39 projecting downwardly beyond the shoulder 38 to cooperate with a lug 21. The inner surface of the tongue 39 may bear inwardly against the peripheral surface of the section IT. The tongue 39 is sufficiently long to have extensive cooperation with a side surface of a lug 27. Means is provided for preventing upward displacement of the lock part 34 from the groove 28. Threaded sockets 48 are provided in the inner or bottom walls of the groove portions 39. After the arrangement of the lock part 39 in a groove 28 a set screw 4| may be threaded in the socket 40 of the groove at the upper end of the lock part. The set screw 4| positively prevents upward shifting of the lock part in the groove 23. The upper outer corner of the lock part 34 may be bevelled off as illustrated in the drawing.

When the sections I6 and I? of the shank are assembled they may be tightly threaded together so that the upper end of the section I! abuts the shoulder 24. The lock part 34 is then slipped in a groove 28 which lies in a vertical plane adjacent the forward side of a lug 2'1 relative to the direction of rotation of the tool. The lock part 34 is fitted downwardly in the groove until the tongues 36 have tight proper cooperation with the flanges 3| and the shoulder 3'! bears against the shoulder 33. The shoulder 38 may cooperate with the upper end of the section IT. The tongue 39 then projects downwardly to be engageable by the adjacent lock 2'! to positively prevent unthreading of the sections I6 and I1. The set screw 4| may be threaded in the socket 48 to prevent displacement of the lock part 34.

The bit head or cutter I2 is provided on the lower end of the shank ID to cut a pilot bore in the earth formation or to operate in a previously formed bore to center the tool. The cutter I2 includes a body or shoe .2 provided with a threaded socket 43 for receiving the pin 25. The shoe 42 may be threaded on the pin until its upper end bears upwardly against the shoulder 26. The cutter !2 includes cutting parts or blades 44 on the shoe 42. In practice the cutter I2 may 1 have any desired number of spaced blades 44. In the particular case illustrated in the drawing there are three equally spaced cutting blades 44. The blades 44 project downwardly and outwardly from the shoe 42 and have lower cuttin edges 45 and side or reaming cutting edges 43. The lower cutting edges 45 may be inclined upwardly and inwardly and may be notched. The reaming edges 46 may be straight and substantially vertical. The upper outer corners of the blades 44 are preferably bevelled or cut away as illustrated in Fig. 1 of the drawing. Spaced ports 4'! are provided in the lower wall of the shoe 42 to discharge the circulation fluid downwardly between the cutting blades 41.

The means I3 for locking the cutter I2 against detachment from the shank ID is similar to the means described above. The means I3 includes one or more grooves 28 in the lower portion of the section I 7 above the pin 25. Where there are three circumferentially spaced blades 44 on the cutter I2 there may be two diametrically opposite grooves 28. The grooves 28 may be identical in configuration to the grooves 28. A key or lock part 34 is adapted to be arranged in a groove 28 to cooperate with or be engageable by a cutting blade 44. The key 34 may be of the same shape as the key 34. Longitudinal dovetailed tongues 3| are provided on the lock part 34 to cooperate with dove-tailed flanges 3|= on the side walls of a groove 28 A downwardly facing shoulder 31 is provided on the inner side of the lock part to cooperate with an upwardly facing shoulder 33 on the inner wall of a groove. A second downwardly facing shoulder 38 may be provided on the inner side of the lock part 34 to cooperate with the upper end of the shoe 42. The lock part 34 has a lower end portion in the form of a tongue 39 which projects downwardly beyond the shoulder 33 for cooperating shoe is threaded on the pin 25.

with a cutting part or blade 44. A threaded socket 40 is provided in the bottom wall of each groove 28 to receive a set screw 4| for locking the part 34 against upward movement.

After the shoe 42 has been tightly threaded on the pin 25 so that its upper end bears against the shoulder 25 the lock part 34 may be arranged in a groove 28 to have its tongue 39 adjacent the forward side of a blade 44. The two diametrically opposite grooves 2t are related to the three equally spaced blades 44 so that a groove occurs adjacent the forward side of a blade when the The lock part 34 may be passed downwardly in the groove 28 until its tongues 36 cooperate with the flanges 3H to tightly lock the part against movement. The shoulder 33 and the upper end of the shoe 42 positively limit the downward movement of the lock part while a set screw 4 l may be threaded in a socket 4|) to prevent upward movement of the lock part. The projecting tongue 39 in front of a blade 44 dependably prevents unthreading of the cutter |2 from the shank.

The cutter I4 is provided to ream and enlarge the well bore. The cutter l4 includes a tubular body 5!) threaded on the portion 59 of the shank section "5. The cutter body 5! is preferably threaded on the portion 59 to a position where its upper end tightly bears against the shoulder 2|. A plurality of spaced cutting blades 5| is provided on the cutter body 5!). The blades 5| project outwardly or radially from the cutter body 5|] and have lower cutting edges 52 and outer cutting edges 53. The lower cutting edges 52 engage or operate on theshoulder of the earth formation occurring between the rathole or pilot bore and the larger upper portion of the bore. The edges 52 may be straight and substantially horizontal. The outer cutting edges 53 are adapted to engage the side wall of the well bore and may be straight and substantially vertical. The upper outer corners of the cutting blades 5| are bevelled or cut away.

The means |5 for locking the cutter |4 against unthreading from the shank I0 is similar to the means II and I3. The lock means I 5 includes a plurality of spaced grooves 28 in the section It above the threaded portion |9. The grooves 28 have intermediate portions provided at their side walls with dove-tailed flanges 3| Upwardly facing shoulders 33 are provided on the bottom walls of the grooves 28 at the lower ends of the flanges 3| The grooves 28 include lower portions 32* extending downwardly through the flange 20 to the shoulder 2|. The number and spacing of the grooves 28 depend upon the number and spacing of the blades 5| of the cutter M. The grooves 28 are spaced and related so that one of them occurs in a plane adjacent a blade 5! regardless of'the rotative position assumed by the cutter body 50 when properly threaded on the section It.

The lock means |5 includes a lock part 34 similar to the lock parts 34 and 34 The lock part 34 is shaped and proportioned to fit one of the grooves 28'. The upper side portions of the lock part 34 are provided with dove-tailed tongues 36 for cooperating with the flanges 3| A downwardly facing shoulder 31 is provided on the inner side of the lock part 34 to cooperate with the shoulder 33 of one of the grooves. A reduced tongue 39 projects from the lower end of the lock part and provides a downwardly facing shoulder 38 on the inner side of the lock part for engaging the upper end of the cutter body 59.

When the cutter body 50 has been tightly threaded on the shank portion H! to a position where its upper end engages the shoulder 2| the lock part 34 may be inserted in a groove 28* that occurs adjacent a cutting blade 5!. The cooperation of the shoulder 33* with the shoulder 31 and the cooperation of the shoulder 38 with the upper end of the cutter body 5| limits the downward movement of the lock part. The tongues 38 cooperate with the flanges 3t to prevent the outward displacement of the lock part from the groove. A set screw 4| may be threaded in a socket 49 in the bottom of the groove to prevent upward movement of the lock part 34*. When the lock part 34 is properly set in position its tongue 39' is engageable by a cutting blade 5| to prevent unthrea-ding of the cutter body 58 from the shank section It.

It is believed that the utility and practicability of the well tool construction will be readily apparent from the foregoing detailed description. It is to be noted that the shank sections and the cutters may be threaded together in the usual manner and then positively locked against detachment or disconnection by the lock means of the invention. The lock means may be employed to lock the parts against unthreading without special manipulation of the parts or sections of the tool. The lock parts 34, 34 and 34 are effectively supported in their grooves against lateral strains or twists through the engagement of their side surfaces with the side walls of the grooves. The dove-tailed tongues of the lock parts cooperate with the dove-tailed flanges on the walls of the grooves to prevent outward displacement of the lock parts. The lock parts are held against longitudinal movement by the cooperation between the shoulders on their inner sides and the shoulders of the grooves and by the set screws in the upper portions of the grooves. The provision of the lock means does not necessitate expensive modification of the tool or redesigning of the cutting elements. The construction of the present invention is adapted for embodiment in various types of well drilling tools and equipment and is not limited in its application to the specific class of tools illustrated in the drawing.

Having described only a typical preferred form and application of our invention, we do not wish to be limited or restricted to the specific form and application herein set forth, but wish to reserve to ourselves any modifications or variations that may appear to those skilled in the art or fall within the scope of the following claims:

Having described our invention, we claim:

1. A well tool including two sections threaded together, at least three circumferentially spaced projections on one section, the other section having at least two circumferentially spaced grooves, and means for locking the sections against unthreading including a removable lock part adapted to be arranged in one of the grooves to project therefrom for cooperation with a projection, the projections and grooves being related so that a groove is located adjacent the plane of a projection to receive the lock part to cooperate with the projection when the sections are properly threaded together.

2. A well tool including two threadedly connected sections, at least three ciroumferentially spaced cutting parts on one section, there being at least two circumferentially spaced grooves in the other section, and means for preventing disconnection of the sections including a lock part adapted to be arranged in one of the grooves to project therefrom for cooperation with an adjacent cutting part.

3. A well tool including two threadedly con nected sections, at least three circumferentially spaced cutting parts on one section, there being at least two circumferentially spaced grooves in the other section, and means for preventing disconnection of the sections including a lock part adapted to be arranged in one of the grooves to project therefrom for cooperation with a cutting part, and means for retaining the lock part in the groove, the cutting parts and grooves being related so that one of the grooves is adjacent the plane of one of the projections to receive the lock part for cooperating with said projection when the sections are tightly threaded together.

4. A Well tool including two threadedly connected sections, at least three circumferentially spaced projections on one section, there being at least two circumferentially spaced grooves in the other section, flanges on the walls of the grooves, and means for preventing unthreading of the sections including a key insertable in one of the grooves to project therefrom and have cooperation with an adjacent projection, tongues on the key to cooperate. with the flanges to prevent outward movement of the key, and means holding the key against longitudinal movement in both directions.

5. A well tool including a shank, a tubular cutter body threaded on the shank, at least three circumferentially spaced blades on the cutter body, there being ciroumferentially spaced grooves in the shank, and means for locking the cutter body against unthreading from the shank including an elongate key insertaole downwardly in a groove and adapted to project therefrom to cooperate with a blade, the number and circumferential disposition of the blades and grooves being such that a groove is positioned adjacent the plane of a blade to receive the key when the cutter bcdy is threaded to position on the shank, and means for preventing upward movement of the key in the groove.

JESSE C. WRIGHT. JOHN H. HOWARD. 

